The invention pertains to a device for sealing damaged walls of containers or tubes that leak. It comprises an inflatable sealing cushion which covers the site of the leak. It is provided with a flexible counter plate which on opposite edges has fastening arrangements for a clamping device surrounding the container of the tube. It also embraces an inflatable inner space or ring on the side of the flexible counter plate which faces the leaking side of the tube. This space is accessible from a nipple located outside and is limited by at least one wall that is composed of a rubber-like reinforced material.
This device, designated throughout this document as a device for sealing leakages, is familiar from German Patent Document 27 45 506. In it the counter plate has ideally the shape of a rectangle, and metal rods are inserted into the shorter ends of the rectangle. These metal rods are embraced by a reinforcing that runs in the direction of the longer sides of the rectangle, the attachments of the clamping and reinforcing device being locked to these metal rods.
When employed, the device for sealing damaged and/or leaking sections is mounted by means of the clamping and reinforcing attachments over the leaking section and secured. The inner section of the device is then filled with compressed air or, alternatively, a liquid under pressure In this way the sealing cushion acquires a greater volume and it presses with its lower edge around the portion of the wall that surrounds the leaking section At the same time, it tightens the belts or ropes of the clamping and reinforcing device. Thus, when inflated, the device ensures that a sealing edge is created by the sealing device on the areas of the wall that surround the leaking section The leaking section is thereby sealed off. In this way, leakages of dangerous materials from containers or tubes that have been damaged can be stopped within a relatively short time Subsequent damage that might result--pollution of the environment or explosions--can thus be avoided.
U.S. Pat. No. 3,496,963 also pertains to a sealing device for tubes. In this device, the inflatable cushion that covers the leakage is surrounded on its outer surface by a matching piece that is constructed as a collapsible bell. This bell has a clamping device that is fitted with a moveable/rotatable threaded bolt By tightening the attached nut, the shell can be put under pressure, whereupon the device lies snugly on the tube. The inflatable cushion is firmly attached to its matching part. Essentially, this device is suited for application on cylindrical bodies, and then only for those of a certain diameter; it is unsuitable for general container shapes, for example, containers that are hauled by semi-trailers. One particular disadvantage of the sealing devices that are already in use is that they are used simply to seal a leak, but do not render it possible to extract in some way or pump off the liquid or the gas that is present at the leak site. But this is frequently necessary when accidents occur involving tanker loads A tanker that has been thrown off its wheels often lies in such a position that access to the actual tanker supports is not possible, access being perhaps blocked by other objects, for example, other vehicles or bridges or earthen walls or walls of houses. It is then difficult, and sometimes even impossible with the means that are at one's disposal, to empty the tank that has been sealed off by the sealing device In this way, further rescue attempts can be prevented or even appreciably delayed; especially if, for example, the tank of the vehicle that has suffered an accident contains a dangerous explosive liquid. The problems described here occur, for example, in accidents involving tankers that are transporting gasoline.
The invention addresses this problem. Its purpose is to develop the cushion that is noted in the introduction in such a way that, while the cushion still effects a good seal around the leaking section, a liquid or a gas can be pumped off or respectively discharged via the sealing cushion.
Proceeding from the cushions for sealing leaks that is noted in the introductory remarks this task is solved by having the inner space configured as a ring. Together with the flexible counter plate, it defines a trough or depression that surrounds the leaking section, and an access passage ensures that the inner space of this trough is connected to the outside of the cushion for sealing leaks.
In contrast to the cushions for sealing leaks that are already known and that are described in the introductory remarks, this cushion for sealing leaks does not contact over its total surface area the leaking section and the regions of the damaged walls that completely surround the leak; rather, it makes contact outside the point of leakage and fits snugly on the damaged wall as a ring around the leak. In this way, a hollow space is created between the damaged wall and the cushion for sealing leaks when the latter is placed against a damaged wall. Whereas in the cushions for sealing leaks that are already familiar, it is not possible to create this space because these cushions are in contact over their total surface area with the surface to which they are applied. Expressed in different words: the cushion for sealing leaks that is constructed in accord with the terms of this invention lies like a bell around the leaking section. It constitutes the trough which is filled by the liquid which streams from the leak. Thus, the trough becomes a collecting basin for discharged fluid, and by means of the access that is planned in accord with this invention, the fluid that collects in the trough can be removed.
The fact that the cushion for sealing leaks makes contact by virtue of the ring-shaped inner space in a ring around the leak (contact is no longer over the total surface area), further ensures that the cushion for sealing leaks cannot be damaged by sharp-edged sections which comprise the edge of the leaking section In all, the device for sealing leaks that is in accord with this invention can be employed in all those instances for which the devices for sealing leaks described above could also be employed It can be applied simply and in very many different situations--even when space is severely limited--and it can be stored both without problem and in a minimum of space. In contrast to the devices for sealing leaks that are already known, it has the added advantage that it does not make contact, or makes less contact, with the edge of the leak. That allows liquid or, respectively, gas, to be drawn off.
The term "ring-shaped" is not to be understood as delimiting solely a circle but rather every possible closed area configuration, especially oval ring, a rectangular ring, et cetera The size of the cushions for sealing leaks--and here there is no difference to the cushions for sealing leaks that are already known conforms to the size of the typically occurring leak For practical application oblong-rectangular cushions for sealing leaks with the dimensions 30.times.60 cm have proven to be suitable and practical By reason of the reinforcing of its walls, the inner space is so capable of withstanding pressure that, even when inflated and applied only loosely and without bracing to a wall, it will not burst when subjected to the maximum pressure The flexible counter plate adapts itself extensively to the curvature of the damaged wall. The clamping devices make it possible to attach it even to the external walls of containers, thereby ensuring that the cushion for sealing leaks does not, when correctly applied, slip sideways away from the leaking section.
Two essentially different types of construction are proposed for the cushion for sealing leaks that is in accord with the invention: In the first version, the cushion for sealing leaks is composed of the flexible counter plate and an inflatable ring that is joined to this counter plate and that is constructed of reinforced rubber material which, for example, is in the shape of a tire, but ideally is rectangular or, respectively, oval in shape In the other version, the cushion for sealing leaks is constructed of layered, hoop-shaped rubber material that is reinforced. The cushion for sealing leaks consists essentially of two walls, a cushion wall that faces away from the leak and a cushion wall that faces to the leak These walls can hang together as one piece or can be cut separately. When cut separately, both walls of the cushion should be reinforced in different directions so that the wall of the cushion that faces the leak can extend itself more forcefully than the wall that faces away from the leak. Both the walls of the cushion are linked not only around the edges but also in the center where the trough is formed. Thus, when inflated, they constitute a body which resembles an inflatable rubber boat. In such a construction, it is advantageous to mount, on the side of the cushion that faces the leak, in the region of the inflatable inner space, a ring-shaped seal that totally surrounds the inner space, for example, a sealing lip or raised edge of rubber material, or one or more sealing edges, and so on. They ensure that no leakages occur between the cushion for sealing leaks and the damaged wall. These leakages occur because the cushion for sealing leaks becomes stiffer when inflated and takes on its own shape, i.e., it no longer is as flexible as it was when uninflated.
In contrast to suction bells, which when applied to leaking sections of damaged containers or tubes, work with negative pressure, the cushion for sealing leaks that is constructed in accord with the invention enjoys the advantage of a higher degree of adhesive/sealing pressures and a closed inner space The higher adhesive pressures are achieved by means of fill pressures which total several times--for example, six times--atmospheric pressure.
Further advantages and characteristics of the invention derive from the remaining claims sought and from the following description of three types of the invention, these types being understood as not limiting in any way the invention. These types are described in more detail below with reference to the drawings.